Pen



FIG. 1 is a perspective view of a pen showing my new design;

FIG. 2 is a right side elevational view of the pen of FIG. 1;

FIG. 3 is a left side elevational view of the pen of FIG. 1;

FIG. 4 is a rear elevational view of the pen of FIG. 1;

FIG. 5 is a front elevational view of the pen of FIG. 1;

FIG. 6 is a top plan view of the pen of FIG. 1; and,

FIG. 7 is a bottom plan view of the pen of FIG. 1.

The broken lines are included to show portions of the pen that form no part of the claimed design. 

CLAIM The ornamental design for a pen, as shown and described. 